From what I read in the article, I could possibly see justification up until he was on the ground. On the ground, while he didn’t comply to their commands, he was not an active resister at that time, but was instead a passive resister. There are definitely techniques that I could see being performed once he was on the ground that don’t include a baton strike. As the subject changes how they are acting, the officers need to adjust as well. That did not happen here.
As for the officers being suspended with pay, that’s not exactly right. They are put on administrative leave, which basically means they lose their police powers while the investigation is performed. Yes, they get paid, but they lose out on all overtime, which many cops rely on as part of their pay. This is done because unlike those of us with regular jobs, using force is part of their job. If every time an officer was suspended without pay because someone complained about a use of force or that the officer did something wrong, it would severely impact the officer’s ability to make a living. I’ve seen cases where officers involved in a shooting have been in limbo for a year only to have their shooting deemed to be justified (in one case he was in a shootout with a subject that had just robbed a store and fired on the officer when he exited the store). Until the officer is found in violation of a policy or charged with a crime, they are going to continue to be paid.